Authorization

Like other Google REST APIs, the Library API uses
OAuth 2.0 to handle authentication and authorization.
Your app can request access to the user's Google Photos library via the various
authorization scopes provided by the API.

Note that the Library API does not support service accounts; to use this API, users must
be signed in to a valid Google Account.

Using the Library API

Before you get started on your app development, keep the following in mind: